First, I'm venturing that this is a gas fireplace with artificial logs, given the appearance of the logs, the proximity to combustible construction and the absence of a sparkscreen, which would be necessary for a wood burning firepit in most jurisdictions.

There are "kits" for gas firepits, meaning off-the-shelf components, but it generally takes a professional to put everything together safely. Working with gas is dangerous, especially if you are working with propane.

It looks like the firepit base is wrapped in steel and the top is cut stone. It could also be concrete. The finish materials should be able to be found locally, but if not, your local fireplace experts should be able to help you with a project like this.
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What Houzz contributors are saying:

A winding steel and Cor-Ten staircase winds its way up to a second-floor balcony. The curved wall around the firepit is made of rusted Cor-Ten, as is the firepit itself. Yates used full range bluestone for the terrace and for the fire-pit cap. The wood boardwalks — another beach-inspired element — are made out of Ipe, a sustainable wood. "This was a rare client in that he asked the design team to take chances, think boldly, and bring him a creative and edgy design that would still fit into the fabric of a somewhat sleepy seaside surfing community," says Yates.

A boardwalk can help bring diagonals into a circular or straight space. These intersecting boardwalks provide movement to the left of the space while creating the opportunity for a water garden at the top of the frame.

while this example is a bit far-fetched in terms of style suitable for your project, it nonetheless shows the transition between wood and stone. here the bluestone is cut to right angle and mortared on a concrete base, for a more regular and formal look (this process is slightly more expensive than that set on sand).

A boardwalk can help bring diagonals into a circular or straight space. These intersecting boardwalks provide movement to the left of the space while creating the opportunity for a water garden at the top of the frame